Commonly referred to as VO2 max testing, respiratory exchange measurement requires a skilled technician, a steady-state exercise environment (treadmill or stationary bicycle), a heart rate monitor, a sealed ventilation mask for the collection of respiratory oxygen (O2) and carbon dioxide (CO2) gases associated with inhalation and exhalation, collection hardware with O2 and CO2 sensors, and a computer with specialized software for the accumulation, interpretation and presentation of the collected data. Measurement of O2/CO2 values allows for the determination of metabolism and is the sine qua non for the accurate quantification of the amount of fat or carbohydrate consumed at specific heart rates from rest through anaerobic efforts. This information is used to understand an individual's metabolic profile and is a valuable and critical tool in many medical, nutrition and exercise settings. Given the technical skills, extensive equipment, and facility requirements, there is a paucity of testing centers and a high fee associated with the administration of respiratory exchange tests. Collectively, these factors represent a significant barrier to the widespread use of respiratory exchange testing, despite the overwhelming need throughout the general population. Specifically, respiratory exchange testing is critical to nutrition and diet planning, and an invaluable tool for weight loss and nutrition maintenance.